我正在尝试从预构建数据库中打开文件。该数据库大约为 40-50 MB。我已经编写了将数据库从 Assets 复制到外部文件的代码。但是无法加载数据库。
我的数据库类
package com.example.foodmed3;
import android.annotation.SuppressLint;
import android.app.Application;
import android.content.Context;
import android.content.res.AssetManager;
import android.database.Cursor;
import android.database.sqlite.SQLiteDatabase;
import android.database.sqlite.SQLiteException;
import android.database.sqlite.SQLiteOpenHelper;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.lang.reflect.Array;
import java.text.DecimalFormat;
@SuppressLint("SdCardPath")
public class DatabaseConnect extends Application
{
private static final String DATABASE_NAME = "facts.db";
private static final String DATABASE_PATH = "/data/data/FoodMed3/databases/";
private static final int DATABASE_VERSION = 1;
private static Context context;
public static SQLiteDatabase db;
public DatabaseConnect(Context paramContext)
{
context = paramContext;
}
public void copyDataBase()
throws IOException
{
InputStream localInputStream = context.getAssets().open("facts.db");
FileOutputStream localFileOutputStream = new FileOutputStream("/data/data/FoodMed3/databases/facts.db");
byte[] arrayOfByte = new byte[1024];
while (true)
{
int i = localInputStream.read(arrayOfByte);
if (i <= 0)
{
localFileOutputStream.flush();
localFileOutputStream.close();
localInputStream.close();
return;
}
localFileOutputStream.write(arrayOfByte, 0, i);
}
}
private boolean dbExists()
{
try
{
SQLiteDatabase localSQLiteDatabase2 = SQLiteDatabase.openDatabase("/data/data/FoodMed3/databases/facts.db", null, 0);
SQLiteDatabase localSQLiteDatabase1 = localSQLiteDatabase2;
if (localSQLiteDatabase1 != null)
localSQLiteDatabase1.close();
boolean bool = false;
if (localSQLiteDatabase1 != null)
bool = true;
return bool;
}
catch (SQLiteException localSQLiteException)
{
while (true)
{
SQLiteDatabase localSQLiteDatabase1 = null;
}
}
}
@SuppressLint("SdCardPath")
public void openDB()
{
OpenHelper localOpenHelper = new OpenHelper(context);
if (dbExists())
{
// db =context.getAssets().open("facts.db");
db = SQLiteDatabase.openDatabase("/data/data/FoodMed3/databases/facts.db", null, 0);
return;
}
db = localOpenHelper.getWritableDatabase();
try
{
copyDataBase();
db = SQLiteDatabase.openDatabase("/data/data/FoodMed3/databases/facts.db", null, 0);
return;
}
catch (IOException localIOException)
{
}
throw new Error("Error copying database");
}
private static class OpenHelper extends SQLiteOpenHelper
{
OpenHelper(Context paramContext)
{
super(paramContext, "facts.db", null, 1);
}
public void onCreate(SQLiteDatabase paramSQLiteDatabase)
{
}
public void onUpgrade(SQLiteDatabase paramSQLiteDatabase, int paramInt1, int paramInt2)
{
}
}
public Cursor searchFoods(String paramString1)
{
Cursor localCursor = null;
String str1 = paramString1.replace("'", "").replace("/", "").replace("\\", "").replace("%", "").replace(">", "").replace("<", "").replace(";", "").replace(":", "").replace("?", "");
String str2 = "";
String[] arrayOfString2 = null;
int i1 = 0;
int i3 = 0;
// label114:
// Cursor
// localCursor;
int i = 0;
int j = 0;
String[] arrayOfString1 = null;
if (str1.contains(" "))
{
arrayOfString2 = str1.split(" ");
i1 = 0;
int i2 = arrayOfString2.length;
i3 = 0;
if (i3 >= i2)
{
// if (paramString2.length() > 0)
// str2 = str2 + " AND FdGrp_Cd='" + paramString2 + "' ";
localCursor = db.rawQuery("SELECT _id, FdGrp_Cd, Long_Desc, NDB_No FROM FOOD_DES WHERE " + str2 + " ORDER BY FdGrp_Cd='0900' DESC, FdGrp_Cd='1100' DESC, FdGrp_Cd='0500' DESC, FdGrp_Cd='0100' DESC, FdGrp_Cd='1500' DESC, FdGrp_Cd='1300' DESC, FdGrp_Cd='1700' DESC, Long_Desc ASC LIMIT 300;", null);
i = 0;
j = localCursor.getColumnIndex("Long_Desc");
arrayOfString1 = new String[localCursor.getCount()];
localCursor.moveToFirst();
}
}
while (true)
{
if (localCursor.isAfterLast())
{
//return localCursor;
String str4 = arrayOfString2[i3];
if (str4.length() > 1)
{
String str5 = str4.substring(-1 + str4.length(), str4.length());
if ((str5.toLowerCase().equals(str5)) && (str5.toLowerCase().equals("s")))
str4 = str4.substring(0, -1 + str4.length());
}
if (i1 + 1 < arrayOfString2.length);
for (str2 = str2 + " Long_Desc LIKE '%" + str4 + "%' AND "; ; str2 = str2 + " Long_Desc LIKE '%" + str4 + "%' ")
{
i1++;
i3++;
break;
}
if (str1.length() > 1)
{
int k = -1 + str1.length();
int m = str1.length();
String str3 = str1.substring(k, m);
if ((str3.toLowerCase().equals(str3)) && (str3.toLowerCase().equals("s")))
{
int n = -1 + str1.length();
str1 = str1.substring(0, n);
}
}
str2 = " Long_Desc LIKE '%" + str1 + "%'";
// break label114;
return localCursor;
}
arrayOfString1[i] = localCursor.getString(j);
i++;
localCursor.moveToNext();
}
}
public String[][] getFood(String paramString1)
{
int i = 0;
Cursor localCursor = db.rawQuery("SELECT FOOD_DES.Long_Desc, FOOD_DES.fav, nutr_defin.rdi, nutr_defin.units, nutr_defin.tagname, NUT_DATA.Nutr_Val, nutr_defin.friendly_des, nutr_defin.nutr_grp FROM NUT_DATA JOIN FOOD_DES ON FOOD_DES.NDB_No = NUT_DATA.NDB_No JOIN nutr_defin ON NUT_DATA.Nutr_No=nutr_defin.nutr_no WHERE FOOD_DES._id='" + paramString1 + "' AND nutr_defin.friendly_des!='' AND nutr_defin.nutr_grp!='' ORDER BY nutr_defin.sr_order ASC LIMIT 200;", null);
String[][] arrayOfString = (String[][])Array.newInstance(String.class, new int[] { localCursor.getCount(), 8 });
int j;
int k;
int m;
int n;
int i1;
int i2;
int i3;
int i4;
DecimalFormat localDecimalFormat1;
DecimalFormat localDecimalFormat2;
if (localCursor.getCount() > 0)
{
localCursor.moveToFirst();
j = localCursor.getColumnIndex("Nutr_Val");
k = localCursor.getColumnIndex("friendly_des");
m = localCursor.getColumnIndex("units");
n = localCursor.getColumnIndex("tagname");
i1 = localCursor.getColumnIndex("nutr_grp");
i2 = localCursor.getColumnIndex("Long_Desc");
i3 = localCursor.getColumnIndex("rdi");
i4 = localCursor.getColumnIndex("fav");
localDecimalFormat1 = new DecimalFormat("#,##0.0");
localDecimalFormat2 = new DecimalFormat("#,##0");
if (!localCursor.isAfterLast());
}
else
{
localCursor.close();
return arrayOfString;
}
double d = Double.parseDouble(localCursor.getString(j).trim());
//* (Double.parseDouble(paramString2) / 100.0D);
arrayOfString[i][0] = localCursor.getString(k).trim();
if (localCursor.getString(m).trim().equals(new String("kcal")))
{
arrayOfString[i][1] = localDecimalFormat2.format(d);
arrayOfString[i][2] = localCursor.getString(n).trim();
arrayOfString[i][3] = localCursor.getString(i1).trim();
arrayOfString[i][4] = Double.toString(d);
arrayOfString[i][5] = localCursor.getString(i2).trim();
if (localCursor.getInt(i3) <= 0)
{
// break label510;
Double localDouble = Double.valueOf(100.0D * (d / localCursor.getInt(i3)));
arrayOfString[i][6] = (localDecimalFormat2.format(localDouble) + "%");
}
}
while (true)
{
arrayOfString[i][7] = localCursor.getString(i4);
i++;
localCursor.moveToNext();
// break;
arrayOfString[i][1] = (localDecimalFormat1.format(d) + localCursor.getString(m).trim());
// break label292;
arrayOfString[i][6] = "~ ";
}
}
}
调用数据库类的Activity类
![package com.example.foodmed3;
import android.os.Bundle;
import android.app.Activity;
import android.database.Cursor;
import android.database.SQLException;
import android.text.Editable;
import android.text.TextWatcher;
import android.view.Menu;
import android.view.View;
import android.view.inputmethod.InputMethodManager;
import android.widget.Button;
import android.widget.EditText;
import android.widget.ListAdapter;
import android.widget.ListView;
import android.widget.SimpleCursorAdapter;
public class FoodSearch extends Activity {
private EditText searchinput;
private ListView searchview;
private Button searchbutton;
private DatabaseConnect data;
private String usersearchinput = "";
private ListAdapter ladapter;
@SuppressWarnings("deprecation")
private SimpleCursorAdapter performSearch(String paramString1)
{
FoodSearch.this.data = new DatabaseConnect(this);
FoodSearch.this.data.openDB();
Cursor localCursor = this.data.searchFoods(paramString1);
startManagingCursor(localCursor);
return new SimpleCursorAdapter(this, R.layout.activity_food_search,
localCursor, new String\[\] { "Long_Desc" }, new int\[\] {R.id.foodsearchview});
}
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_food_search);
usersearchinput="";
searchinput = (EditText) findViewById(R.id.foodsearchinput);
searchview = (ListView) findViewById(R.id.foodsearchview);
searchbutton = (Button) findViewById (R.id.foodsearchbutton);
FoodSearch.this.searchinput.setText("");
FoodSearch.this.searchbutton.setOnClickListener(new View.OnClickListener()
{
public void onClick(View paramAnonymousView)
{
FoodSearch.this.usersearchinput = FoodSearch.this.searchinput.getText().toString();
FoodSearch.this.ladapter=performSearch(FoodSearch.this.usersearchinput);
((InputMethodManager)FoodSearch.this.getSystemService("input_method")).hideSoftInputFromWindow(FoodSearch.this.searchinput.getWindowToken(), 0);
FoodSearch.this.searchview.setAdapter(FoodSearch.this.ladapter);
}
});
FoodSearch.this.searchinput.addTextChangedListener(new TextWatcher()
{
public void afterTextChanged(Editable paramAnonymousEditable)
{
}
public void beforeTextChanged(CharSequence paramAnonymousCharSequence, int paramAnonymousInt1, int paramAnonymousInt2, int paramAnonymousInt3)
{
}
public void onTextChanged(CharSequence paramAnonymousCharSequence, int paramAnonymousInt1, int paramAnonymousInt2, int paramAnonymousInt3)
{
FoodSearch.this.usersearchinput = FoodSearch.this.searchinput.getText().toString();
if (FoodSearch.this.usersearchinput.length() > 1)
FoodSearch.this.ladapter=performSearch(FoodSearch.this.usersearchinput);
FoodSearch.this.searchview.setAdapter(FoodSearch.this.ladapter);
}
});
}][1]
logcat 输出
01-13 23:43:05.136: D/libEGL(1426): loaded /system/lib/egl/libGLES_android.so
01-13 23:43:05.147: D/libEGL(1426): loaded /system/lib/egl/libEGL_emulation.so
01-13 23:43:05.156: D/(1426): HostConnection::get() New Host Connection established 0x9365918, tid 1426
01-13 23:43:05.246: D/libEGL(1426): loaded /system/lib/egl/libGLESv1_CM_emulation.so
01-13 23:43:05.246: D/libEGL(1426): loaded /system/lib/egl/libGLESv2_emulation.so
01-13 23:43:05.297: W/EGL_emulation(1426): eglSurfaceAttrib not implemented
01-13 23:43:05.336: D/OpenGLRenderer(1426): Enabling debug mode 0
01-13 23:43:05.606: I/dalvikvm(1426): threadid=3: reacting to signal 3
01-13 23:43:05.606: I/dalvikvm(1426): Wrote stack traces to '/data/anr/traces.txt'
01-13 23:43:37.237: D/Food(1426): Food Tab switched
01-13 23:43:37.877: D/Food(1426): Food Search clicked
01-13 23:43:37.967: W/EGL_emulation(1426): eglSurfaceAttrib not implemented
01-13 23:43:38.047: D/OpenGLRenderer(1426): Flushing caches (mode 0)
01-13 23:43:38.857: I/SqliteDatabaseCpp(1426): sqlite returned: error code = 14, msg = cannot open file at line 27701 of [8609a15dfa], db=/data/data/FoodMed3/databases/facts.db
01-13 23:43:38.857: I/SqliteDatabaseCpp(1426): sqlite returned: error code = 14, msg = os_unix.c: open() at line 27701 - "" errno=2 path=/data/data/FoodMed3/databases/facts.db, db=/data/data/FoodMed3/databases/facts.db
01-13 23:43:38.857: E/SqliteDatabaseCpp(1426): sqlite3_open_v2("/data/data/FoodMed3/databases/facts.db", &handle, 2, NULL) failed
01-13 23:43:38.857: E/SQLiteDatabase(1426): Failed to open the database. closing it.
01-13 23:43:38.857: E/SQLiteDatabase(1426): android.database.sqlite.SQLiteCantOpenDatabaseException: unable to open database file
01-13 23:43:38.857: E/SQLiteDatabase(1426): at android.database.sqlite.SQLiteDatabase.dbopen(Native Method)
01-13 23:43:38.857: E/SQLiteDatabase(1426): at android.database.sqlite.SQLiteDatabase.openDatabase(SQLiteDatabase.java:1013)
01-13 23:43:38.857: E/SQLiteDatabase(1426): at android.database.sqlite.SQLiteDatabase.openDatabase(SQLiteDatabase.java:986)
01-13 23:43:38.857: E/SQLiteDatabase(1426): at android.database.sqlite.SQLiteDatabase.openDatabase(SQLiteDatabase.java:962)
01-13 23:43:38.857: E/SQLiteDatabase(1426): at com.example.foodmed3.DatabaseConnect.dbExists(DatabaseConnect.java:58)
01-13 23:43:38.857: E/SQLiteDatabase(1426): at com.example.foodmed3.DatabaseConnect.openDB(DatabaseConnect.java:80)
01-13 23:43:38.857: E/SQLiteDatabase(1426): at com.example.foodmed3.FoodSearch.performSearch(FoodSearch.java:31)
01-13 23:43:38.857: E/SQLiteDatabase(1426): at com.example.foodmed3.FoodSearch.access$3(FoodSearch.java:28)
01-13 23:43:38.857: E/SQLiteDatabase(1426): at com.example.foodmed3.FoodSearch$1.onClick(FoodSearch.java:55)
01-13 23:43:38.857: E/SQLiteDatabase(1426): at android.view.View.performClick(View.java:3511)
01-13 23:43:38.857: E/SQLiteDatabase(1426): at android.view.View$PerformClick.run(View.java:14105)
01-13 23:43:38.857: E/SQLiteDatabase(1426): at android.os.Handler.handleCallback(Handler.java:605)
我的AndroidManifest.xml
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.example.foodmed3"
android:versionCode="1"
android:versionName="1.0" >
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />
<uses-sdk
android:minSdkVersion="8"
android:targetSdkVersion="15" />
<application
android:allowBackup="true"
android:icon="@drawable/ic_launcher"
android:label="@string/app_name"
android:theme="@style/AppTheme" >
<activity
android:name="com.example.foodmed3.TabLayout"
android:label="@string/app_name" >
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
来自 SQLLite 数据库浏览器的我的数据库内容
我们将不胜感激。
谢谢。
最佳答案
我认为您的 DATABASE_PATH 不正确。文件系统上的路径将基于您的包名称，因此它应该是 /data/data/com.example.foodmed3/databases/
关于Android数据库错误(android.database.sqlite.SQLiteCantOpenDatabaseException : unable to open database file)，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/21103816/